This section provides background information to facilitate a better understanding of the various aspects of the disclosure. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
Agricultural harvesting machines such as combine harvesters are used to reap, thresh, and winnow grain crops such as wheat, rye, barley, corn, soybeans, oats, flax, sunflower, canola, and the like. More specifically, combine harvesters are used to cut grain crops at the base, separate the grains from the remainder of the plant (the chaff), and sort the grain from the chaff. These machines require special adaptations to accommodate specific crops, navigate through field landscapes, and resist damage from the crops, stone, and the elements; especially moisture and high temperature which can lead to the degradation of the machine's rubber components.
Generally, combine harvesting machines gather crops using a header as the machine moves through a field. The header may be one of several types, each of which provides a means of gathering a particular type of crop. The header is connected to a feederhousing which provides a means of conveying the crop to a threshing mechanism which is part of the harvesting machine.
In one type of header which is useful for small grain, the gathered crops are pushed by a reel into a cutter bar, which runs the length of the header and is equipped with teeth made of metal or plastic to cut crops at their base. Headers may have a rigid or flexible header platform depending upon the operator's needs. Flexible header platforms, or “flex headers” have a cutter bar which is capable of flexing over uneven terrain. Machines using flex headers are most often used to cut soybeans, whereas conventional header platforms have a rigid cutter bar and are most often used to cut cereal crops. Freshly cut crops fall behind the cutter bar and onto a plurality of draper belts which are wrapped around parallel spaced rollers. Draper belts function primarily to consolidate crops and move the crops within the header towards a feederhousing, which then conveys the crops to a threshing mechanism. Alternatively, the freshly cut crop may be conveyed within the header to the feederhousing by augers.
A second type of header is useful for row crops such as corn. This type of header has dividers which define crop gathering gaps for each crop row. In each gap, the ears of corn containing the corn grain kernels is removed from the corn stock and is conveyed by auger or belt to the feederhousing. The stalk and other plant residue are separated from the ears and remain in the field so that the amount of material processed by the threshing mechanism is minimized.
A third type of header is useful for crops which have been previously cut and collected for drying or other aging in the field. This type of header includes a pick-up apron to convey the cut crop into the header and onto a plurality of draper belts which are wrapped around parallel spaced rollers. The draper belts function primarily to consolidate crops and to gently move the crops within the header towards a feederhousing, which then conveys the crops to the threshing mechanism.
For each header type, the feederhousing movably supports the header and connects it to the threshing mechanism contained in the main body of the combine harvester. The feederhousing includes a closed channel, typically of rectangular cross section, having an inlet opening at the forward end which engages the header at the point where the header discharges the crop. The feederhousing has a discharge opening at the rearward end which engages the desired inlet area of the threshing mechanism. The crop is conveyed within the closed channel of the feederhousing from the header to the threshing mechanism by bars or cleats which are attached to chains or belts. The chains or belts are supported by a shaft and sprockets near the discharge opening, and by one or more shafts or drums near the inlet opening. Rotation of the belts or chains about the shafts moves the bars or cleats in a closed loop path from the inlet to the discharge. The moving bars or cleats carry or drag the crop from the header to the threshing mechanism.
Additional mechanisms within the feederhousing may be used to assist the conveyance of the crop. They may guide the path of the bars or cleats or chains, allow limited motion of the drums, and/or control the tension of the chain. The bars and belts or chains are subject to abrasive wear from contact with the crop, and to damage from foreign object that inadvertently enter the feederhousing. Belts made in a continuous loop are difficult to install in a traditional feederhousing, so an assembly of belts and bars in which the continuous loop can be opened for installation is useful.
Inside the threshing mechanism, the grain is separated from the plant stems, cobs, straw, leaves, and chaff. The threshed grains are collected in a grain collecting tank, and the plant waste, or chaff, is moved to discharge openings of the threshing mechanism for disposal to the field or for collection if desired as a secondary product.
Other harvesting machines are used for cutting silage. The header of this machine usually is made to engage with row crops, but instead of striping ears from the stalk, the stalk is cut near the ground and the entire plant is conveyed to the feederhousing. The feederhousing conveys the plant to a chopping mechanism instead of a threshing mechanism to produce animal feed.
Some problems with the use of chains to convey crops within the feederhousing are high weight, excessive noise generation while in operation, chain wear, and chain stretch. Accordingly, there is an ongoing need for improved feederhousing components which improve on the current problems in the art, the need met at least in part, by embodiments according to the disclosure.